Vibration actuated contact switch



- June 18, 1968 L. A. GUTHART VIBRATION ACTUATED CONTACT SWITCH FiledJune 30, 1966 M m" A frim w 3 Pk 1 7 l r 7 Ill/17 zVA/A /1/6 7111/ ByATTORNEY UnitedStates Patent 3,389,236 Patented June 18, 1968 VIBRATIONACTUATED CONTACT SWITCH Leo A. Guthart, Old Westbury, N.Y., assignor toAlarm Device Manufacturing Company, a Division of Pittsburgh RailwaysCompany, Inc., Carle Place, N.Y., a

corporation of Pennsylvania Filed June 30, 1966, Ser. No. 561,977 4Claims. (Cl. Nil-61.48)

This invention relates to a vibration actuated switch incorporatingnovel means for securing the switch in unitary transversely keyedrelation to a planar surface and for actuating the same on vibration ofsaid planar surface. The switch thus actuates an electrical circuit, tosignal acts such as for example, the applying of tools to the planarsurface, or breaking or cutting the surface, forced entry, or otherwisevibrating the surface.

The switch is provided with parallel transverse serrations formed on therear surface thereof to be thereby secured in keyed relation to theplanar surface to be monitored and is sealed by a cover readily appliedthereto, sealing the contacts and other parts thereof.

The switch is effective and reliable in operation, easy to install andrugged and durable in use.

The drawings, illustrating procedures and devices useful in carrying outthe invention, and the description below, are exemplary only of theinvention, which shall be deemed to cover all other devices andprocedures coming within the scope and purview of the appended claims.

In the drawings, wherein similar reference characters indicate likeparts:

FIG. 1 is a perspective view of a vibration actuated contact switchembodying the invention, shown secured to a planar surface whosevibration is to be monitored thereby, and showing also the leads to asignaling circuit controlled by the switch,

FIG. 2 is a transverse, vertical, sectional view thereof taken at line2-2 of FIG. 1,

FIG. 3 is an enlarged, fragmentary, sectional view of parts thereofcorrespondingly shown in FIG. 2,

FIG. 4 is a top plan view thereof, taken at line 4-4 of FIG. 2, and

FIG. 5 is a bottom plan view thereof, taken at line 55 of FIG. 2.

As shown in the drawings, the switch of this invention comprises anelongated base member (FIGS. 2, 3) having formed coextensive with theouter planar face 16 thereof, a plurality of transverse serrations 19formed transversely of the longitudinal axis of the face 16 andsubstantially coextensive therewith, for adhering contact with theplanar plate surface 17 (FIGS. 1 and 3) to be monitored by the switch,as, for example, by an adhesive 18 applied (FIG. 2) to surface 16 so asto fill the interstices between the transverse serrations 19 andextending therebeyond, for transversely locking and keying the switch tothe planar surface 17. To that end adhesive 18 may have readilyevaporating volatile solvents. The adhesive layer, after application,dries to form the switch body and planar surface 17 into a solid,homogeneous unit with a plurality of related or parallel transverse keying interstices thus assuring essentially integral direct transmissionof the vibrations of surface 17 along the transverse serrations 19,actuating the switch as below set forth. Leads 20 (FIG. 1) are connectedto the switch contact 34 (through 28, 25, 29) and contact 31 (through 33FIG. 2) as below described. On vibration of the planar surface 17 asbelow described, the switch is actuated to control a circuit into whichthe leads 20 are cut, for actuating a warning signal or other electricalapparatus.

An elongated bracket (FIG. 3) is secured at one end, as at 26, to thebase member 15 interiorly of the switch and opposite the transverselyserrated outer face 16 thereof. The bracket 25 has an opposite free end27, preferably offset therefrom. An elongated, flexible, vibratory strip28 is fixed, at one end, to the interior of the base member inelectrical contact with the end of the bracket, as through means 29,said strip having a free end 30 extending beyond the opposite end 27 ofthe bracket and in line with and spaced from a first contact 31, securedto the elongated base member 15 as at 32 (FIG. 2). A second contact 34is secured to the flexible vibratory strip 28, as shown in FIG. 3, inline with the said first contact 31. Contacts 31, 24 may be of silver orother corrosion-resistant materials. A weight 35 may be secured to theflexible strip 28 at the said free end 30 thereof, for enhancing thependulum reciprocation action of strip 28 on vibration of the surface17, enhancing the switch-closing action on vibration of the switch.Adjustable means, such as screw 37, may be secured to the free end 27 ofbracket 25, to contact and move the vibratory strip 28 to a preciselydesired position, to thereby predetermine the exact spacing of thecontacts 34 and 31 and thus the degree of vibration necessary to closethe switch (dotted lines, FIG. 3).

The switch may be scaled by a cover 38, bolt 39 passing through thecover and engaging a threaded socket 41 or the like in the base member15 (FIGS. 3 and 2).

The cover 38 is thus closed tightly and in dust-sealing relation to theswitch body, effectively sealing the contact points againstcontamination. Said serrations 19 define, in use, a plurality ofrelated, keying, interstices with which the adhesive 18 interlocks,keying the switch to surface 17. To that end the serrations 19 areinterrelated in an arrangement to assure the elfective keying actiondescribed. Dne example of such arrangement is shown in FIG. 5 whereinthe serrations 19 are arranged in parallel, spaced relation. They may bespaced in an arrangement other than parallel, as may be desired, todefine interstices for achieving the adhesive keying action above noted.The example of transverse spaced parallel serrations 19 above noted isthus intended to illustrate a convenient form of carrying out theinvention, which is not limited thereto and may be embodied in otherforms pursuant to and embodying the invention.

While the foregoing disclosure of exemplary embodiments is made inaccordance with the Patent Statutes, it is to be understood that theinvention is not limited thereto or thereby, the inventive scope beingdefined in the appended claims.

I claim:

1. A vibration actuated contact switch comprising an elongated basemember having an outer planar surface, serrations formed on said surfacein relation to a planar plate surface for adhering keying contacttherewith so that the vibration of said plate surface will be monitoredby said switch, a bracket secured to the interior on the base memberopposite and in parallel spaced relation to said serrated surface, acontact mounted in said switch, an elongated flexible strip fixed at oneend to the interior of the base member with the other end being free,and freely movably extending in line with and spaced from said contact,means engaging the bracket and flexible strip for adjusting the positionof the latter relative to said contact, whereby, on positioning theswitch with said serrated face adhered to a planar surface to bemonitored, and connecting said switch contact and flexible strip with acircuit, vibration of said planar surface will correspondingly vibratethe switch and thus said flexible strip will flex into engagement withsaid contact, actuating said circuit.

2. In a vibration actuated contact switch for connection with a circuitto be controlled thereby as set forth in claim 1, a second contact,fixed to the said free end of the flexible strip, for engagement withthe first menticned contact on so flexing the strip.

3. In a vibration actuated contact switch for connection with a circuitto be controlled thereby as set forth in claim 1, a weight fixed to saidflexible strip to enhance reciprocating pendulum movement thereof onvibration of said switch.

4. In a vibration actuated contact switch for connection with a circuitto be controlled thereby as set forth in claim 1, a second contact fixedto the flexible strip in line with the first mentioned contact forclosing thereon on said flexing of the flexible strip, and a weightfixed to the free end of the flexible strip to enhance the reciproeatingpendulum movement thereof.

References Cited UNITED STATES PATENTS 10 ROBERT K. SCHAEFER, PrimaryExaminer.

M. GINSBURG, Assistant Examiner.

1. A VIBRATION ACTUATED CONTACT SWITCH COMPRISING AN ELONGATED BASEMEMBER HAVING AN OUTER PLANAR SURFACE, SERRATIONS FORMED ON SAID SURFACEIN RELATION TO A PLANAR PLATE SURFACE FOR ADHERING KEYING CONTACTTHEREWITH SO THAT THE VIBRATION OF SAID PLATE SURFACE WILL BE MONITOREDBY SAID SWITCH, A BRACKET SECURED TO THE INTERIOR ON THE BASE MEMBEROPPOSITE AND IN PARALLEL SPACED RELATION TO SAID SERRATED SURFACE, ACONTACT MOUNTED IN SAID SWITCH, AN ELONGATED FLEXIBLE STRIP FIXED AT ONEEND TO THE INTERIOR OF THE BASE MEMBER WITH THE OTHER END BEING FREE,AND FREELY MOVABLY EXTENDING IN LINE WITH AND SPACED FROM SAID CONTACT,MEANS ENGAGING THE BRACKET AND FLEXIBLE STRIP FOR ADJUSTING THE POSITIONOF THE LATTER RELATIVE TO SAID CONTACT, WHEREBY, ON POSITIONING THESWITCH WITH SAID SERRATED FACE ADHERED TO A PLANAR SURFACE TO BEMONITORED, AND CONNECTING SAID SWITCH CONTACT AND FLEXIBLE STRIP WITH